a—The 1906 Intercalated Games in Athens are considered unofficial by the IOC because they did not take place in the four-year cycle established in 1896. However, most record books include these interim games with the others.

b—The 1940 Summer Games are originally scheduled for Tokyo, but Japan resigns as host after the outbreak of the Sino-Japanese War in 1937. Helsinki is the next choice, but the IOC cancels the Games after Soviet troops invade Finland in 1939.

c—Germany and Japan are allowed to rejoin the Olympic community for the first Summer Games since 1936. Though a divided country, the Germans send a joint East-West team until 1964.

d—The Soviet Union (USSR) participates in its first Olympics, Winter or Summer, since the Russian revolution in 1917 and takes home the second most medals (22-30-19—71).

e—Due to Australian quarantine laws, the equestrian events for the 1956 Games are held in Stockholm, June 10-17.

f—East Germany and West Germany send separate teams for the first time and will continue to do so through 1988.

g—The 1976 Games are boycotted by 32 nations, most of them from black Africa, because the IOC will not ban New Zealand. Earlier that year, a rugby team from New Zealand had toured racially segregated South Africa.

h—The 1980 Games are boycotted by 64 nations, led by the USA, to protest the Soviet invasion of Afghanistan on Dec. 27, 1979.

i—The 1984 Games are boycotted by 14 Eastern Bloc nations, led by the USSR, to protest America's overcommercialization of the Games, inadequate security and an anti-Soviet attitude by the U.S. government. Most believe, however, the communist walkout is simply revenge for 1980.

j—Germany sends a single team after East and West German reunification in 1990 and the USSR competes as the Unified Team after the breakup of the Soviet Union in 1991.